"row1@abc.com,venki@abc.com,vr@xyz.com",field2,field3,field4
row2r@xyz.com,field2,field3,field4
field1,"row3@abc.com,venki@abc.com, vr@xyz.com",field3,field4
field1,"1111@abc.com,row4@abc.com",,field4
field1,"1111@abc.com""1234,999,row5@abc.com",,field4

Row:1,NF=4, "row1@abc.com,venki@abc.com, vr@xyz.com", field2, field3, field4
Row:2,NF=4, row2r@xyz.com, field2, field3, field4
Row:3,NF=4, field1, "row3@abc.com,venki@abc.com, vr@xyz.com", field3, field4
Row:4,NF=4, field1, "1111@abc.com,row4@abc.com", , field4
Row:5,NF=6, field1, "1111@abc.com""1234, 999, row5@abc.com"